Saturday, 18 October 2014

Creationist Abomination - Lesbian Lizards

Cnemidophorus-ThreeSpecies.jpg

Photograph by Alistair J. Cullum. Via Wikimedia Commons
Of course, Intelligent Design 'Theory' has nothing to do with religion or the Bible, does it, creationists! No! Intelligent design is all based on good science and has no fundamentalist religious agenda at all. Intelligent Design 'Theory' would be just the same even if all the proponents of it weren't religious fundamentalist who believe Genesis is the inerrant word of a magic creator and the best available description of reality.

Or that's what they would have their non-fundamentalist victims believe anyway.

Similarly, it's merely a coincidence that proponents of IDT are invariable against same-sex relationships and agree with the the Bible that homosexuality is a mortal sin. And it's naturally no coincidence that the god of the Christian Bible agrees with IDTists because the Bible is science and what they are dealing with is science, not religion at all... isn't it?

So, what's all this about lesbian lizards? Doesn't the creator hate homosexuality?

Let's look at the facts:

The so-called New Mexico whiptail lizard (Cnemidophorus neomexicanus) is one of about 50 reptiles that normally breed parthenogenically (i.e. without mating) to produce clones of themselves. All these lizards are female. In fact, although parthenogenesis is the normal way of producing new C. neomexicanus there is one less common way. It's the way the first ones were formed - by two other species mating to produce a hybrid. Genetics has shown that C. neomexicanus arose, and still arises occasionally, when the two bisexual species, the little striped whiptail (C. inornatus) and the western whiptail (C. tigris), which have overlapping ranges, mate naturally.

So, what's this, creationists? Here is a new species which can arise by a simple mating between two other species! That's the thing that you're supposed to believe is impossible because some mysterious, unspecified, process related to the laws of thermodynamics makes it impossible. Reguar readers may remember me writing about the edible frog (Pelophylax kl. esculentus) which can only breed with difficulty with members of its own species and so females needs to mate with a member of another species, usually the pool frog (P. lessonae) or sometimes the marsh frog (P. ridibundus) to get more edible frogs. I don't recall seeing how that fact fitted in with a creationist claim that it's impossible either.

But our little whiptail lizard from New Mexico doesn't even need to mate with members of another species because, unlike edible frogs, but just like many other lizards, many of which have also arisen by hybridization, it doesn't need to mate at all. It simply lays fertile eggs which contain a full set of its genes and which hatch out into identical clones of itself.

C. neomexicnus mating.
But it doesn't stop there. All the New Mexico whiptail lizards are female and yet they go in for lesbian sex in which one adopts the 'normal' male role and the other the female, after which they both produce their eggs. There is some evidence that this act of pseudocopulation helps stimulate egg production even though nothing is passed between them. In these reptiles, like most birds, copulation consists of pressing the cloaca together and doesn't involve penetration.

Frankly, this looks superficially like a bit of a paradox for evolutionary biologists because the usual reason given for sexual reproduction having evolved and being the 'normal' mode of reproduction in the vast majority of multicellular animals is that the ensuing genetic mixing increases the likelihood of a beneficial mutation arising and ensures genetic diversity is maintained, so enabling the species to adapt more readily to a changing environment. So why then does clonal parthenogenesis seem to arise in some orders?

The answer seems to be that this mode of reproduction enables a parthenogenic species to move into a new range very quickly from a single individual. In bisexual species, one of each sex has to come into contact at the right time in the new range for a population to get started. It has often been noted that parthenogenesis is more often to be found in unusual or 'difficult' environments. And of course, we don't know if species such as the New Mexico whiptail would last long in evolutionary terms if the population isn't continually renewed through new hybridization. Some species are known to have several gene lines, indicating that each is derived from a new hybridization event.

A review of our current knowledge of teioid unisexuals and their hybrid origins is provided. Also, a reevaluation of teiine chromosomal evolution is presented from a phylogenetic perspective. These reviews elucidate the paradox that the capability of instantly producing parthenogenetic clones through one generation of hybridization has existed for approximately 200 million years, yet the extant unisexual taxa are of very recent origins. Consequently, these lineages must be ephemeral compared to those of bisexual taxa.


So, we know that the ability of these taxa to instantly produce a unisexual clonal species in a single generation has been around for 200 million years, and yet we know that all the known unisexual species are recent in origins. This suggests a short-term success but long-term lack of evolutionary viability, so there is actually no paradox in the detail. Rather, the facts appear to bear out the idea that sexual reproduction is the more successful strategy notwithstanding that parthenogenesis can give relatively stable short-term success.

So, no problem there for evolutionary science which understands that genes don't have moral scruples or conscious thought of any kind, let alone planning and forethought. However, given the invariably literal interpretation of the Christian Bible by creationists, even those who claim their creationism has nothing to do with religion and is all good, sound science which just happens to be fully in accord with the Bible, how does this all fit in please? Doesn't the god in the Bible supposedly abhor homosexuality, finding the act so abominable that people who do it deserve to be killed? - (Leviticus 20:13)

And didn't the god in the Bible supposedly create all the animals, including the lesbian whiptail lizard from New Mexico? - (Genesis 1:24)

Any creationist with the courage to explain all this and how it fits in the the 'science' of 'Intelligent Design Theory'? Does this god enjoy a bit of casual perving, maybe?





submit to reddit



3 comments :

  1. Thank you, Rosa, for this very informative post/news! BTW: Here's a partly related topic: http://www.economist.com/news/science-and-technology/21626398-copulation-older-most-biologists-suspected-girls-and-boys-come-out-play?fsrc=nlw%7Cnewe%7C20-10-2014%7C .

    It's about how internal fertilisation (= copulation) evolved from external fertilisation and how the act of copulation is much older than previously believed. Probably at least 385 million years old. The fish, now extinct, is called Microbrachius dicki (maybe an appropriate name?). M. dicki is a member of the most primitive sub-group of a group of fish called placoderms.

    ReplyDelete
    Replies
    1. Thanks, I already have a blog in the pipeline on that topic.

      Delete
  2. Then maybe also this article is worth reading and pondering: http://pleiotropy.fieldofscience.com/2014/10/evolution-sex-and-mixability.html ?

    ReplyDelete

Obscene, threatening or obnoxious messages, preaching, abuse and spam will be removed, as will anything by known Internet trolls and stalkers or by known sock-puppet accounts.

A claim made without evidence can be dismissed without evidence. Remember: your opinion is not an established fact unless corroborated.

Related Posts Plugin for WordPress, Blogger...
Web Analytics